Electric motors are powered by driving waveforms generated by motor control subsystems. Under certain conditions, motors can experience faults such as abnormal current conditions. Fault protection schemes identify faults and may respond to them by shutting off the motors.
For example, an over-current condition occurs when the current flowing to a motor exceeds a predetermined maximum amount. Hardware-based protection schemes exist for identifying and responding to such a fault condition. Such a scheme may be implemented by a power module component of the motor control subsystem, and may involve sensing a voltage signal associated with the driving waveform, comparing the voltage signal to a predetermined maximum voltage signal, and based thereon, determining whether an over-current condition exists (by Ohm's law, the voltage is representative of the current). If such a condition is determined to exist, then the power module may use hardware to initiate a response that causes the motor to shut off. However, if a problem occurs with the hardware, then the protection scheme may fail to identify or properly respond to the fault condition such that the motor continues to operate under the abnormally high current condition.
This background discussion is intended to provide information related to the present invention which is not necessarily prior art.